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ag·no·sia

(ăg-nōzhə)

Loss of the ability to interpret sensory stimuli, usually leading to the inability to identify or recognize objects using one or more senses.

[Greek agnōsiā, ignorance : a-, without; see A–¹ + gnōsis, knowledge (from gignōskein, to know; see gnō- in the Appendix of Indo-European roots).]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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